Does YAML Validator upload my input?

No. This tool runs in your browser unless the privacy badge explicitly says a server route is required.

Can I use this for production secrets?

Avoid pasting sensitive production data into any website. Prefer local test data or redacted payloads.

Can YAML be valid but still wrong?

Yes. Syntax can pass while required service fields, config keys, or runtime-specific values are missing.

Why include Docker Compose diagnostics here?

Compose files are YAML, but deployment review also needs services, images, build paths, ports, volumes, environment, dependencies, and a shareable report that avoids raw environment values.

YAML Validator - Free Online Data Tool

yaml validatorvalidate yamlyaml checkeryaml syntax checkerPrivacy: Browser local

YAML Validator

Validate YAML syntax, format YAML, and inspect Docker Compose services for config, CI, and documentation files.

Input / Output

Start with the tool

Input, output, and copy actions stay in this main surface. Examples and reference checks are separated below.

Copy-ready output

YAML examples

Input bytes

Lines

Document type

Object

Top-level entries

Review notes

YAML syntax and common indentation checks look ready.

Docker Compose checks

Inspect services, image/build coverage, ports, volumes, environment, and depends_on before copying a Compose file.

Compose status

Not detected

Services

Images

Build services

Published ports

Volume mounts

Environment entries

Compose review notes

Compose service checks look ready for local validation or formatting.

YAML deployment report

Copy a safe YAML or Compose handoff report with config shape, service counts, warnings, and deployment checks.

Input bytes

Lines

Document type

Object

Top-level entries

Compose status

Not detected

Services

Images

Build services

Published ports

Volume mounts

Environment entries

Raw YAML body included

No, the full YAML body is excluded.

Raw environment values included

No, environment values are excluded.

Review notes

No YAML or Compose review warnings detected. Confirm runtime behavior in the target environment.

Deployment checklist

Run the formatted YAML through the target tool such as docker compose config, CI, or hosting validation.
Check environment values in a separate secret-safe review; this report does not include raw environment values.
Confirm published ports, host path mounts, and dependencies match the deployment environment.
After deployment, verify the public URL, DNS, and server response instead of trusting YAML parsing alone.

# YAML deployment report

- Checked at: Browser copy time
- Input bytes: 47
- Lines: 5
- Document type: Object
- Top-level entries: 3
- Compose status: Not detected
- Services: 0
- Images: 0
- Build services: 0
- Published ports: 0
- Volume mounts: 0
- Environment entries: 0
- Raw YAML body included: No, the full YAML body is excluded.
- Raw environment values included: No, environment values are excluded.

## Service preview
- Not applicable

## Review notes
- No YAML or Compose review warnings detected. Confirm runtime behavior in the target environment.

## Deployment checklist
- Run the formatted YAML through the target tool such as docker compose config, CI, or hosting validation.
- Check environment values in a separate secret-safe review; this report does not include raw environment values.
- Confirm published ports, host path mounts, and dependencies match the deployment environment.
- After deployment, verify the public URL, DNS, and server response instead of trusting YAML parsing alone.

Related tools

Useful next steps

Next step:

ENV CheckNext step: Validate .env snippets and copy a raw-value-free deployment report before moving values into hosting or CI settings.YAML JSONNext step: Convert configuration snippets between YAML and JSON.JSONNext step: Format compact API responses before copying them into code or docs

Output

Validation result

Copy-ready output

Valid YAML

Parsed preview:
{
  "name": "Bob",
  "active": true,
  "items": [
    "json",
    "yaml"
  ]
}

Output

Formatted YAML

Copy-ready output

name: Bob
active: true
items:
  - json
  - yaml

Local session

Input state is saved only in this browser so you can restore the last workspace without an account.

Review after the result

Open examples, checks, and related tools only after the primary input/output flow is done.

Web operations workbench

Validate deploy config

Validate YAML or Compose structure, inspect environment values, then format JSON config fragments before shipping.

3 Tools

1. YAML Check
Check indentation, YAML parse errors, and Compose service diagnostics.
2. ENV Check
Review duplicate, malformed, empty, or secret-like environment values.
3. JSON
Format JSON config fragments and inspect shape before copying.

Before copying

Validate the small pasted block before committing the full config file.
Preview the parsed JSON shape and check arrays, nested maps, booleans, and null values.
Continue to YAML JSON Converter or JSON Schema Validator when the config needs conversion or structural checks.

Common failure cases

Indentation can look aligned in a copied config while the parsed object nests keys under the wrong parent.
YAML accepts unquoted values such as yes, no, on, and off differently across tooling versions.

Guides

JSON, YAML, and CSV conversion workflow

Review after the result

Open examples, checks, and related tools only after the primary input/output flow is done.

Guides

Examples

Starting points for this utility

name: Bob
active: true

services:
  app:
    image: node:20
    ports:
      - "3000:3000"

items:
  - id: 1
    enabled: true

Use cases

Data

Validate YAML syntax before committing config files.
Inspect Docker Compose services, images, ports, volumes, environment, and dependencies.
Format parsed YAML into copy-ready output after reviewing warnings.

Validate the small pasted block before committing the full config file.
Preview the parsed JSON shape and check arrays, nested maps, booleans, and null values.
Continue to YAML JSON Converter or JSON Schema Validator when the config needs conversion or structural checks.